Revenue - Revenue by Major Species (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Revenue from External Customer [Line Items]
Revenue		$ 2,190	$ 2,000
Contract manufacturing & human health
Revenue from External Customer [Line Items]
Revenue		20	17
Companion animal
Revenue from External Customer [Line Items]
Revenue		1,450	1,225
Companion animal | U.S.
Revenue from External Customer [Line Items]
Revenue		898	721
Companion animal | International
Revenue from External Customer [Line Items]
Revenue		552	504
Livestock
Revenue from External Customer [Line Items]
Revenue		720	758
Livestock | U.S.
Revenue from External Customer [Line Items]
Revenue		265	284
Livestock | International
Revenue from External Customer [Line Items]
Revenue		455	474
Operating Segments | U.S.
Revenue from External Customer [Line Items]
Revenue		1,163	1,005
Operating Segments | International
Revenue from External Customer [Line Items]
Revenue	[1]	$ 1,007	$ 978

[1] Revenue denominated in euros was $223 million and $204 million for the three months ended March 31, 2024 and 2023, respectively.